Diseases of the heart valves are grouped according to which valve(s) are involved and the way that blood flow is disrupted. The most common valve problems occur in the mitral and aortic valves. Diseases of the tricuspid and pulmonary valves are fairly rare.
The aortic valve regulates the blood flow from the heart's left ventricle into the aorta. The aorta is the main vessel that supplies oxygenated blood to the rest of the body. Diseases of the aorta can have a significant impact on an individual. Examples of such diseases include aortic regurgitation and aortic stenosis.
Aortic regurgitation is also called aortic insufficiency or aortic incompetence. It is a condition in which blood flows backward from a widened or weakened aortic valve into the left ventricle of the heart. In its most serious form, aortic regurgitation is caused by an infection that leaves holes in the valve leaflets. Symptoms of aortic regurgitation may not appear for years. When symptoms do appear, it is because the left ventricle must work harder as compared to an uncompromised ventricle to make up for the backflow of blood. The ventricle eventually gets larger and fluid backs up.
Aortic stenosis is a narrowing or blockage of the aortic valve. Aortic stenosis occurs when the valve leaflets of the aorta become coated with deposits. The deposits change the shape of the leaflets and reduce blood flow through the valve. The left ventricle has to work harder as compared to an uncompromised ventricle to make up for the reduced blood flow. Over time, the extra work can weaken the heart muscle.